The proposed investigation is aimed at acquiring information on the nutritional implication of modified food starches. The objectives of the project are to: (1) determine the effect of modified starches in the diet on the microflora and the pH of the small and large intestines during growth and development, (2) determine the effect of processing and storage treatments applied to these starches in foods on the microflora and the pH of the intestine, (3) determine the significance of changes in microflora on the availability of nutrients for absorption, (4) identify the digestion products of modified starches and determine their metabolic fate in the body, and (5) determine what dietary components are chelated by modified starch and describe the factors which affect chelation. The predominating intestinal microflora of animals on modified starches will be identified. The type of nutrient that these microorganisms can metabolize, their synthetic activities and the resulting products will be studied in vitro. Biochemical, radiotracer and electron microscopy techniques will be applied in vitro and in vivo to determine digestion, absorption and metabolic products of modified starches. The chelation of minerals and other low molecular weight nutrients by modified starches will be evaluated by atomic absorption spectroscopic and radiotracer procedures. The nutritional significance of this chelation phenomenon will be determined by in vitro and in vivo digestion studies. The effect of processing and storage treatments on the complexing of nutrients by modified starches will be studied.